Cardiovascular disease is a leading cause of death in the United States. During the last few decades, a number of treatment methods and devices have been developed to combat the disease and treat the resulting complications.
One method developed to treat cardiovascular disease is local therapy at the site in question. Delivery catheters have been used extensively in delivering local therapy. For example, they can be used to deliver stents, grafts, therapeutic substances and radiopaque agents to a desired location within the patient's vasculature.
Therapeutic substances such as cells and other bioactive materials are often introduced into the tissue in question in order to treat a disease or condition. Various methods of cell delivery have been employed with varying degrees of success. Direct cell delivery has been used when an increased cell density is desired at the target site. Although direct cell delivery has been shown to increase the number of viable cells in some target locations, a significant problem still exists when the cells are delivered to localized vasculature. When cells and/or bioactive materials are delivered to blood vessels, a majority of the delivered materials dissipate or redistribute from the target site due to the natural flow of blood through the vessel. Specific targeted delivery of cells such as stem cells to the treatment area can also be a challenge. Circulating blood can wash out the stem cells that are injected to a target site such as a heart muscle wall.
Therefore, a need exists for improved cell delivery to blood vessels in the human body that overcomes these and other disadvantages.